1. Field of the Invention
The present invention relates generally to electronics used in telecommunications applications, and particularly to an improved apparatus and methods for installing and operating a digital subscriber line (DSL) system.
2. Description of Related Technology
As is well known, Asymmetric Digital Subscriber Line (ADSL), and Very high bit rate Digital Subscriber Line (VDSL) can provide broadband access to various nodes (e.g., homes and small offices) “piggybacked” on the existing telephone lines. Currently, data rates of up to 8 Mbit/s are possible with ADSL. VDSL utilized on shorter loops can provide data rates up to 50 Mbit/s.
More recently, efforts have been made to provide additional voice lines over DSL (so-called “voice-over-DSL” or VoDSL). Using this approach, it is possible to provide many dial tone channels over DSL. However, a significant concern under such approaches is continuity of service and reliability of electrical power to the various subscriber entities served by the DSL infrastructure. Typical prior art ADSL/gateway approaches (FIG. 1) require local power, or local backup power, to supply power during outages. These approaches are comparatively costly, thereby raising the cost of providing DSL service to the service provider and/or subscriber. Additionally, backup power sources are not always (properly) maintained or available, and thus not entirely reliable.
Another consideration relates to data networking at the subscriber's site. Wireless interfaces and home phone networking (HPN) systems have become increasing prevalent. Wireless systems, including those compliant with IEEE Standards 802.11A and 802.11B or the more recent Bluetooth/3G standards, are designed to allow wireless interface between one or more mobile or remote units such as laptop computers, personal digital assistant (PDA), or telephone, without the need for telephone line infrastructure or other networking devices. These systems are often characterized by a local gateway or base station which facilitates two-way communication between the mobile/remote unit(s) and the network to which the gateway is connected, as well as between individual mobile/remote units.
Home phone networking (HPN) systems, also commonly referred to as “HomePNA”, allow data interchange between various locations within a localized site such as a residence or small business. HPN systems are generally based on the specifications developed by the Home Phone Networking Alliance (HPNA). HPNA Standard 1.0, the original version of the standard, sets forth specifications for systems operating at 1 Mbps. A more version of the standard, HPNA 2.0, is based on technology developed by, inter alia, Broadcom, and operates at a faster data rate of 10 Mbps. Even faster variants are presently being contemplated. Advantages of HPN systems include ease of installation, low cost, the ability to have multiple nodes on the network, compatibility with existing networking and PC technologies, and effectively constant data rate (largely independent of concurrent telephone voice signals). HPN systems also have the advantage of obviating expensive and complex server, hub, and router devices. HPN systems require that a phone jack be physically located near the desired location of each computer, gateway, or other network node, and generally has limitations on the length of interposed wiring between the various HPN nodes.
Despite there advantages, the foregoing wireless and HPN systems must be supplied with electrical power derived from the local power system (i.e., utility provided power service), or from a separate subscriber-maintained power supply. Loss of electrical service interrupts wireless/HPN system operation unless an uninterruptible power supply (UPS) or similar device is maintained, the latter representing a significant cost and maintenance issue for the subscriber.
Another recent initiative known as HomePlug™ seeks to standardize the use of existing power lines present in subscriber homes or offices as a means of transferring data between various network nodes at the site. Power lines are currently a pervasive home networking medium, and are available worldwide, thereby affording the use of multiple outlets in a given structure at a lower cost per connection point. Additionally, the convenience of connecting any device through a power outlet has a certain attraction.
Despite the foregoing initiatives and emergence of VoDSL, no technology at present makes effective use of the existing power line infrastructure and telecommunications wiring infrastructure to allow for interoperability between HPN, wireless, HomePlug-capable, and traditional data networking systems, while also addressing the issue of electrical power continuity.
Based on the foregoing, an improved apparatus and method of providing reliable, continuous power to the subscribers of DSL systems (including VoDSL systems) is needed. Such improved apparatus and methods would (i) be readily implemented by the subscriber, (ii) make use of existing telecommunications and/or power line infrastructure, and (iii) be compatible with a variety of different device types and configurations present at the subscriber site, such as standard telephones, multi-line digital telephones using home phone network (HPN) systems, wireless, and HomePlug compatible devices.